There is no way to scale down to the width of a line on the printer (168 pixels, I think) from 200 or 400 pixels smoothly enough to conserve details on a 1-bit-per-pixel (not greyscale!) printer given the constraints on RAM and code size that the DM42 has to work with.

Thanks for the answer, I understand that a 400x240 picture is not compatible with the printer resolution, however it should be possible to print a 200x120 picture rotated 90° without any need for down scaling as 120 pixels should fit within the 166 pixel maximum width.

Not a big issue, but as PIXEL and AGRAPH have been updated to support the new screen capabilities it would be good to have also PRLCD supporting what could make sense.

PIXEL and AGRAPH have been modified to make use of the whole screen. I don't know the what magic takes place behind the screen, so please let me know if I'm being naïve here, but would it be possible to make PRLCD work for GrMod 2 too? I appreciate that the thermal printer can receive the 131 pixel width screen information from the HP42s and indeed from the DM42, but GrMod 2 is 200x120, so rotated 90°, it would fit. It would mean some backend converting the screen to layers of GrMod 0 LCD, but the printer would be able to handle it.

Not sure how much work it would take to code, or if it'd be a Free42 or a DM42 patch. Might not be possible. Might only be possible with excessive work, which isn't worthwhile or viable. Might be easy to implement and a good addition. I just have no idea.